• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.612-619
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• 2004

A competitive direct enzyme-linked immunosorbent assay (cdELISA) was developed for selective and rapid detection of a glycopeptide antibiotic, teicoplanin (TP). TP was conjugated to bovine serum albumin (BSA) for use as an immunogen. Repeated subcutaneous injections of 0.5 mg of the conjugate was effective in generating specific polyclonal antibody (PAb) toward TP in rabbits, as determined by cdELISA. TP-horseradish peroxidase conjugate (TP-HRP) was used as an enzyme marker. The cdELISA was developed based on a competition reaction between TP-BSA PAb and TP-HRP conjugate. The TP-BSA PAb was highly sensitive (detection limit, 0.3 ng/ml and specific toward teicoplanin, showing no cross-reactivity to other glycopeptide antibiotics including vancomycin. There were good correlations ($r^2$=0.84 and 0.76, respectively) between cdELISA and microbiological assay, and high-performance liquid chromatography. The cdELISA system developed in this work is expected to be useful not only for selective and rapid monitoring of TP but also for study of TP pharmacokinetics.

• 한국식품영양과학회지
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• 제27권6호
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• pp.1152-1159
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• 1998

In order to develop more rapid and reproducible analysis of biotin known as vitamin H, attempts were made to establish the condition for enzyme linked immunosorbent assay(ELISA) compared with traditional microbiological assay(MBA). Antibiotin and antiserum were obtained from the immunized rabbits injected with emulsion of biotin KLH conjugate and Freund's adjuvant. The antiserum showed cross reactivity on biocytin, a derivative of biotin, which is converted to biotin in intestine, at the rate of 177%(median inhibitory concentration(IC50)=12.58ppb), but not on other derivatives such as desthiobiotin, diaminobiotin and 2 imino biotin. Specific antibody for biotin was purified from the antiserum through protein A column and desalting column. The conditions of competitive direct ELISA (cdELISA) were established. Detection range of biotin concentration by cdELISA was 0.01∼300ng/ ml(ppb). In the spike test with milk, fruit flake and pine carrot juice, the correlation coefficient between two methods of MBA and ELISA was reliably consistent at the value of r=0.992. But detection of biotin by microbiological assay(MBA) was rather restricted in range and nonspecific. Detection range of biotin by MBA was 0.1∼0.5ng/ml(ppb). It showed cross reactivities on biocytin and desthiobiotin at the rate of 80.1% and 66.7%, respectively. In conclusion, ELISA revealed a significant improvement compared with MBA for the biotin detection in terms of sensitivity, detection range and cross reactivity. In addition, a variety of samples could be analyzed rapidly and conveniently at one time by using ELISA. These results strongly suggest that the ELISA is very promising for the practical application to detect biotin contents in a wide range of food stuffs.

• 한국식품위생안전성학회지
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• 제13권2호
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• pp.129-134
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• 1998

Nivalenol(NIV)의 검출을 위한 효소면역측정법(ELISA)을 개발하기 위하여 tetraacetyl nivalenol(Ac4-NIV)에 대한 다클론항체를 생산하고 그 조건을 확립하였다. Ac4-NIV-hemisuccinate를 bovine serum albumin에 공유결합 시킨 Ac4-NIV-HS-BSA를 Freund's adjuvant와 함께 수차례 토끼에 피하면역하였다. 가장 높은 항체가를 나타낸 항혈청으로부터 정제한 항체와 Ac4-NIV-HS-HRP conjugate를 이용하여 직접 경합 ELISA(cdELISA)를 확립하였다. 그 표준 곡선으로부터 Ac4-NIV의 검출 범위는 10~5,000 ng/ml(ppb)임을 알 수 있었다. 특이항체의 Ac4-NIV과 acetyl T-2에 대한 반응성은 각각 100, 70%였으나, NIV, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, triacetyl deoxynivalenol, fusarenon-X, T-2에 대한 반응성은 0.1% 이하로 극히 미약하였다. NIV를 인위적으로 오염시킨 옥수수 시료를 70% acetonitrile 추출하고 acetylation 한 다음 cdELISA를 행하였을 때, 분석의 회수율은 100, 300, 1,000 ng/g(ppb)에서 각각 108, 143, and 70%(평균, 107%)로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.877-880
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• 2004

In this study, we determined the content of chitooligosaccharides (COS) in Korean commercial salt-fermented shrimps by competitive direct enzyme-linked immunosorbent assays (cdELISAs), using anti-COS mixture (COSM) antibody and COSM horseradish peroxidase (HRP) conjugate. When COS6 was spiked into salt-fermented shrimps at the level of $10-300\mu{g/g,}$ the average recovery was $120\pm19%$ ($mean\pmS.D.$). The COS contents of the 92 samples of Korean commercial salt-fermented shrimps collected during February 2000 and August 2002 were $36.3\pm20.7\mug$ COS6 equivalent/g (expressed as "$\mug/g$" hereafter). Among the samples, the COS contents of yuk-jeot ( $40.3 \pm 22.5 \mug/g, n=27$) and buksaewoojeot ($40.2 \pm 21.6 \mug/g, n=5$) were higher than the others. The COS contents of salt-fermented shrimps produced at Gwangcheon ($47.1 \pm 20.7 \mug/g, n=18$) and Gomso ($44.1 \pm 21.8 \mug/g, n=6$) areas were higher than those produced at the other areas. This is the first report to determine COS of salt-fermented shrimps by cdELISA.

• 한국미생물·생명공학회지
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• 제25권4호
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• pp.414-419
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• 1997

In order to develop an enzyme-linked immunosorbent assay (ELISA) for deoxynivalenol (DON) in com, we produced a specific monocl- onal antibody and established ELISA conditions. After the spleen cells from mice immunized with DON-bovine serum albumin conjugate were fused with S$_{p}$2/0 myeloma cells, a hybridoma cell 3G7 producing anti-DON antibody was screened by ELISA. From the standard curve of competitive direct ELISA (cdELISA) using 3G7 monoclonal antibody and DON-HRP conjugate, the detection range of DON showed 3-3,000 ng/ml (ppb). The monoclonal antibody showed some cross-reactivities against DON analogues such as 15 acetyl-DON (110%), nivalenol (5.0%), 3 acetyl-DON (1.7%), fusarenon-x (0.72%), and T-2 (0.59%). When the cdELISA was applied to the spiked coms after extracting with 60% methanol and diluting 5- fold with washing buffer, the assay recoveries of DON were 313, 163, 106, and 88.9% (av., 168%) in the levels of 200, 600, 2,000, and 6,000ng/g, respectively. For the quantitation of DON in coms, 30 samples kept under two different storage conditions of cold and room temperature were assayed by cdELISA. The mean detection concentrations were 595 (detection range, 0-2,750) and 2,448 (detection range, 0-4,500) ppb, respectively.

• 한국미생물·생명공학회지
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• 제24권5호
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• pp.630-635
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• 1996

For a survey of the occurrence of aflatoxin M$_{1}$ (AFM$_{1}$) in domestic cow's milk, we developed an enzyme-linked immunosorbent assay (ELISA) system, and quantitated the toxin in cow's milk. In order to produce specific antibodies AFM, conjugated to bovine serum albumin (AFM$_{1}$-BSA) and Freund's adjuvant were immunized subcutaneously to rabbits. By use of the antiserum showing the highest titer and AFB$_{1}$-HRP conjugate, we established a competitive direct ELISA (cdELISA) for AFM$_{1}$, whose detection limit was 0.003 ppb. The cross-reactivities of the antiserum against aflatoxin M$_{1}$ M$_{2}$, B$_{1}$, B$_{2}$, G$_{1}$, G$_{2}$, B$_{2a}$, and G$_{2a}$, were 100, 29.9, 25.0, 2.7, 13.0, 0.65, 0, and 0%, respectively. When the cdELISA was applied to the cow's milk spiked with AFM$_{1}$ and followed by cleanup with C$_{18}$ cartridge, the mean recovery of the assay was 104% (mean of CV, 6.4%) in the final concentration of 0.01-1 ppb (10-1, 000 ppt). When cow's milk samples gathered from markets and farms were assayed by the cdELISA, the mean concentration and SD of AFM$_{1}$ was 80.4 $\pm$ 55.0 ppt (n=64; range, 5.6-280 ppt).

• 한국식품과학회지
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• 제35권2호
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• pp.291-296
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• 2003

된장 및 간장의 chitooligosaccharide(COS) 함량을 높이기 위해 Bacillus subtilis와 Rhizopus oryzae를 접종하여 koji를 만들고 이들 균주들에 의한 된장 및 간장에서 COS 함량변화에 대하여 알아보았다. COSM에 특이적인 항체를 이용하여 competitive direct ELISA(cdELISA)로 COS를 검출하였는데, 검출 감도는 $0.001{\sim}1{\mu}g/mL$이었고, 회수율은 된장 및 간장에서 각각 102%, 115%를 보였다. B. subtilis koji와 R. oryzae koji를 섞어 담근 된장 또는 간장(BR 된장 또는 간장)이 높은 COS 함량을 보였는데, 두 달 숙성에서 된장이 $171{\mu}g/g$, 간장이$29{\mu}g/mL$을 나타내었다. 일본, 국내 시판, 그리고 실험실에서 만든 된장 및 간장의 COS 함량을 비교해 본 결과, BR 시료구가 일본이나 국내 시판용보다 훨씬 높은 함량을 나타내 주어서 본 실험에서 koji 제조시 이용된 Bacillus subtilis와 Rhizopus oryzae 의해 COS의 함량을 높일 수 있는 가능성을 보여주었다.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.686-692
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• 2004

To develop the enzyme-linked immunosorbent assay (ELISA) for the analysis of N-acetylehitooligosaccharides (NACOS) and chitooligosaccharides (COS), specific antibodies (Abs) were produced, and their properties were compared. N-acetylehitohexaose (NACOS6), chitohexaose (COS6), and COS mixture (COSM) conjugated to bovine serum albumin (BSA) were used to immunize rabbits. By the use of specific Abs and NACOS6-horseradish peroxidase (HRP), COS6-HRP, and COSM-HRP conjugates, competitive direct ELISA (cdELISA) was developed. The detection limits of NACOS6 by the anti-NACOS6 Ab and COS6 by the anti-COS6 and the anti-COSM Abs in the cdELISAs were about 0.2, 2, ana 2 ng/ml (ppb), respectively. In the cdELISA, the anti-NACOS6 Ab was found to recognize NACOS3-NACOS6, but not N-acetyl-D-glucosamine (GlcNAc), NACOS2, and COSs; the anti-COS6 Ab recognized COS2-COS6 and COSM, but not glucosamine (GlcN) and NACOSs. The recognition pattern of the anti-COSM Ab was almost the same as that of the anti- COS6 Ab, except that the former recognized COS2 and COS3 slightly better than the latter.

• 한국식품위생안전성학회지
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• 제18권3호
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• pp.95-100
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• 2003

된장과 고추장에 대해 cdELISA에 의한 $AFB_1$의 분석방법을 확립하고 국내에서 생산되는 재래식 및 개량식 된장과 고추자을 수거하여 $AFB_1$의 오염도를 조사하였다. 표준곡선을 작성하였을 때, 이의 검출 한계는 0.2 ng/m(ppb)이었다. 된장의 Spike test 후 회수율은 1~100 ng/g 범위에서 평균 71.5%로 나타나 이 범위에서 cdELISA에 의한 $AFB_1$의 측정이 가능함을 보여주었다. 이로부터 된장 및 고추장에서 cdELISA를 통한 $AFB_1$의 분석 방법을 확립하였다. 된장 및 고추장 시료의 $AFB_1$의 오염도는 총 30종의 고추장 시료에서는 $AFB_1$이 검출되지 않았고 총 30종의 된장 시료 중 6종에서 1.0~6.0 ng/g 수준으로 검출되었다. 이는 우리 나라의 허용 기준인 10 ng/g(ppb) 이하였다.

• 한국미생물·생명공학회지
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• 제24권1호
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• pp.119-125
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• 1996

In order to develop enzyme-linked immunosorbent assay (ELISA) for fumonisins, production of specific antibodies, establishment of ELISA conditions, and quantitation of the toxin from spiked corns by ELISA were performed. Fumonisin $B_1(FB_1)$ conjugated to cholera toxin (CT) with or without Freund's adjuvant was subcutaneously injected into 2 groups of rabbits. When the titer of the antisera produced by each rabbit was tested, higher titer was observed in case of the immunization with the adjuvant. By use of the antiserum showing the highest titer (1:16,000) and its purified antibodies, competitive indirect and direct ELISA's (ciELISA and cdELISA) were established, respectively. When the cross-reactivity of the antibody against fumonisin analogs was investigated by the ciELISA, it was very low against $B_3$ (2%) but high against fumonisin $B_2$ (179%). The sensitivity of the ELISAs was also very high, because the detection limit for $FB_1$ was 0.03 ppb in ciELISA and 0.3 ppb in cdELISA. When the ELISA's were applied to the spiked corns after extraction with 75% methanol, the assay recovery of $FB_1$ was too unstable to assay. However, when cleanup by strong anion exchange (SAX) cartridge was introduced to remove interfering materials, the mean ELISA recovery of $FB_1$ from corns spiked to 3~10 ppm was found to be 34.0% and stable (mean of CV, 8.2%).